Your database instance is configured with automatic undo management and the UNDO_RETENTION
parameter is set to 900 seconds. You executed the following command to enable retention
guarantee:
SQL>ALTER TABLESPACE undotbs1 RETENTION GUARANTEE;
What affect would this command have on the database?
A.
The extents in the undo tablespace retain data until the next full database backup
B.
The extents containing committed undo in the undo tablespace are not overwritten for at least 15
minutes
C.
The extents containing committed data in the undo tablespace are not overwritten until the
instance is shut down
D.
The extents containing committed undo in the undo tablepace are transferred to Flash Recovery
Area before being overwritten
Retention Guarantee
To guarantee the success of long-running queries or Oracle Flashback operations, you can enable retention guarantee. If retention guarantee is enabled, the specified minimum undo retention is guaranteed; the database never overwrites unexpired undo data even if it means that transactions fail due to lack of space in the undo tablespace. If retention guarantee is not enabled, the database can overwrite unexpired undo when space is low, thus lowering the undo retention for the system. This option is disabled by default.